Gateways are widely used to connect devices at the home to the Internet or any other wide area network (WAN). Gateways use in particular Digital Subscriber Line (DSL) technology that enables a high data rate transmission over copper lines or optical lines. Residential gateways, but also other devices such as routers, switches, telephones and set-top boxes, are understood in this context as Customer Premises Equipment (CPE) devices.
Gateways including wireless technology have a key role in today's home and professional environments. A mechanism for connecting wireless devices to a Local Area Network (LAN) is called Wi-Fi, which is a brand name of the Wi-Fi Alliance for devices using the IEEE 802.11 family of standards for wireless data transmission. The IEEE 802.11 standards define two types of wireless nodes, a general wireless device that can connect to other devices called a station and a special type of station that is in control of the network, namely an access point. A Wi-Fi network, often called a WLAN (Wireless Local Area Network), consists of one or more access points embedded in a gateway connected to one or several stations. Of course, gateways may use other mechanisms for connecting wireless devices to a Local Area Network (LAN).
Due to its flexible and “invisible” nature, a lot of local area network devices are utilizing Wi-Fi rather than the classical wired Ethernet approach. This widespread usage of wireless local area network has exposed however a serious downside of using a shared medium technology: interference. Interference, both Wi-Fi and non-Wi-Fi related, leads to a degraded user experience due to the nature of IEEE 802.11.
An important aspect when configuring a wireless local area network, is the allocation of a frequency channel to a given access point. Auto Channel Selection (ACS) algorithm allows the access points to scan the various frequency channels available and select a frequency channel based on several parameters such as background noise, communication medium business, the number of neighboring access points based on beacon messages received from other access points as well as the Received Signal Strength Indication (RSSI) with which these beacon messages are received, etc.
In environments such as buildings in which access points are densely deployed, those access points influence each other, in particular, by causing interference to one another. In order to provide a frequency channel allocation scheme in such densely populated environments information gathered by the access points are collected in a centralized manner so as to coordinate the frequency channel allocation between the different access points. That information is for example, for a given access point, a list of neighboring access points, the frequency channel allocated to those neighboring access points as well as the respective RSSI, etc.
In case an access point has less neighboring access points than the number of available frequency channels, a straightforward solution consists in allocating non-overlapping frequency channels to each of the neighboring access points. Such a solution cannot be implemented in densely populated environments where an access point has more neighboring access points than the number of available frequency channels.
In such a situation, relying on a list of neighboring access points, background noise, communication medium business, the beacon messages received from neighboring access points as well as the Received Signal Strength Indication (RSSI) with which these beacon messages are received, etc. may lead to a frequency channel allocation scheme that may not significantly reduce the interference between access points because the correlation between interference and the above-mentioned parameters is not well known and/or deterministic.
The present invention has been devised with the foregoing in mind.